NYT article on induction cooking

[Sean]

As many of you know, we have a single tabletop induction hob aboard Odyssey and we love it.  We use it whenever we have electric power available and sometimes even when we don't -- it works so much better for certain dishes that we opt to run it off the batteries.  And I have written here before that if I were converting a bus today, I would skip the LP altogether (on Odyssey, it only runs the two-burner stove and the BBQ grill) and go all-electric, with a pair of 120-volt induction hobs.

Induction has been coming down in price and going up in availability.  When we bought ours six years ago, there were no consumer-grade multi-hob induction cooktops sold in this country, and now there are several.  (Most are not good choices for conversions, though, because they require 240 volts.)  Today I came across the following article in the New York Times which discusses the emerging popularity of induction cooking:

http://www.nytimes.com/2010/04/07/dining/07induction.html?8dpc

Worth a read if you are on the fence about induction.

-Sean
http://OurOdyssey.BlogSpot.com

[Iceni John]

Very interesting.   When the larger Chinese appliance makers such as Haier start to get involved we may see further price reductions, but let's hope they don't cut corners with quality.   I assume all induction cookers are UL listed for sale here.

Sean, what really piqued my curiosity was your mentioning you sometimes power your induction cooker off your house batteries.   What wattage is your cooker, and do you have a 12 or 24 volt house system?   My (long-term) plan is to have up to 1000 W of PV panels on the roof to charge four (or eventually eight) T125 golfcart batteries.   Do you think this amount of AH would be sufficient for a small induction cooker?   Also, does induction require a pure-sine inverter, or can one use a cheaper MSW inverter?   Is your present small table-top hob 12V or 120V?

Like you, I want to keep LPG use to a minimum, for safety and cost reasons.   I also want to minimize build-up of water vapor from burning propane, to reduce condensation issues.

Thanks, John

[Sean]

Lots of info on this in the archives, including my setup, described here:
http://www.busconversions.com/bbs/index.php?topic=7562.msg74502#msg74502

We run that off the inverter, of course, which is a 4kW, 24-volt sine wave model.

I recommend true sine for induction cooktops, for the same reason true sine is better for induction motors: the inductance will otherwise try to fight the voltage changes of the stair-step in an MSW unit, leading to less efficiency and overheating of the coils.  And while it is tempting to think that the whole point of a stove is to heat, in an induction hob, the heat is supposed to happen in the pan, not the induction unit itself.

Including inverter losses, my hob draws about 60 amps from the batteries when it is running full tilt.  Depending on settings, though, the hob will normally be running either at lower power than that, or cycling on and off as needed, so real usage is not as high as 60 amp-hours per hour.  If we had planned to use induction cooking exclusively rather than LP, I think we would have added battery amp-hours.  At a minimum, the space and weight taken up by our 5 gallons of LP would have been given instead to batteries.

More reading on the board:
http://www.busconversions.com/bbs/index.php?topic=7524.msg73808#msg73808
http://www.busconversions.com/bbs/index.php?topic=6866.0
http://www.busconversions.com/bbs/index.php?topic=11220.0

-Sean
http://OurOdyssey.BlogSpot.com

[Skykingrob]

Sean, et all
I have been looking for a 120 volt built in induction cooktop for the past year and haven't come across one. Have you found one by any chance? I read with interest Luverbus "experiment" at splitting the 240 volt unit as I had thought about doing that myself but like him decided not to pursue it.
We are near putting countertop in the unit and the wife has decided to forgo putting in a built in cooktop and just use 1 or 2 portable induction hobs. I actually looked into making "depressions" in the countertop to make the portable units appear built in but found out that ventilation could be a problem and would void the warranty. I am still trying to talk her into putting in a cooktop in the event that the 120 volt induction units are still some time off but not making much progress after seeing how well the induction units work.

Rob
91 Prevost LeMirage XL
Missouri

[ruthi]

We decided not to put in a built in stove top. I rather have the counter. We got a one burner induction that we can take out when we need it. I have one of those nu-wave ovens for cooking. I love it, I use one in the house.

[philiptompkjns]

Sean, et all
I have been looking for a 120 volt built in induction cooktop for the past year and haven't come across one. Have you found one by any chance? I read with interest Luverbus "experiment" at splitting the 240 volt unit as I had thought about doing that myself but like him decided not to pursue it.
We are near putting countertop in the unit and the wife has decided to forgo putting in a built in cooktop and just use 1 or 2 portable induction hobs. I actually looked into making "depressions" in the countertop to make the portable units appear built in but found out that ventilation could be a problem and would void the warranty. I am still trying to talk her into putting in a cooktop in the event that the 120 volt induction units are still some time off but not making much progress after seeing how well the induction units work.

Rob
91 Prevost LeMirage XL
Missouri

http://www.walmart.com/ip/Mr.-Induction-SR-1851C-Induction-Cooktop-White/5982302

[Sean]

I have been looking for a 120 volt built in induction cooktop for the past year and haven't come across one. Have you found one by any chance?  ... I actually looked into making "depressions" in the countertop to make the portable units appear built in but found out that ventilation could be a problem and would void the warranty.

Rob,

Built-in units with multiple hobs on one cooktop are generally going to be 240-volt.  However, you can find single-hob drop-in models that are 120-volt, up to 1,800 watts.  The problem is they are quite spendy, at $450-$700 per hob.  Spring makes a nice selection, for instance:

http://theinductionsite.com/hob-makers/spring-induction-hobs.shtml

By contrast, the Sunpentown counter-top units such as the one Phillip linked above can be had for just over $100.  So having a shallow depression for a pair of these to sit in would be the cheap way to go; just design the "wells" to have plenty of room for the units to ventilate.  You could blow through four of these Sunpentowns before you get up to one drop-in unit.

I am still trying to talk her into putting in a cooktop in the event that the 120 volt induction units are still some time off but not making much progress after seeing how well the induction units work.

Depending on what your countertop material is, the smart way to go would be to set up the counter structure and cabinetry to accommodate drop-in units later, but run the surface material completely over it.  Use the countertop units on top of the surface until you are comfortable with them.  You can always get out the worm-drive and cut an opening later for the drop-in units (or a well) if you decide that's the way you want to go.

-Sean
http://OurOdyssey.BlogSpot.com

[edroelle]

I am with Sean.  Induction is great.  I pull the portable induction unit from the drawer, and rarely use the built-in cooktop.   I would build them in, with a cover and plenty of ventilation.

I have tried my induction cooktop with my Xantrex RV3012 MSW inverter.   It will not work at all.

Ed Roelle
Flint, MI

[Skykingrob]

Thanks Guys
I appreciate the links. I had never come across "theinductionsite.com" in my google searches, the other site referred to at Walmart, I had seen. Unfortunately, she has choosen 2 cm granite countertop, which makes it real hard to try to do something. I did think about having the installers cut out a "standard" size of most builtin cooktops at their shop before bus install, then use the cutout material for a cover which could be later removed and a cooktop dropped in. Again unfortunately, there really isn't a "standard" cooktop size, many are very close but not the same.  Also unfortunately, a worm drive won't do the granite and removing it to take it to the granite shop might just break it.
I guess I will just need to delay this whole countertop process as long as possible to hopefully allow a company to build a 2 burner builtin induction cooktop in 120V, if ever.
It's okay, I need to get the bus off to the paint shop anyway.

Rob
91 Prevost LeMirage XL
Missouri

[luvrbus]

Rob, don't give up on the idea of splitting the 2 units I have hers at a shop now seeing if parts are available to change the units to a 1200 and a 1500w burner will keep you posted.
If your wife is like mine she is going to have the induction mine has been using induction since 2000 and not going to give it up without a battle as for me I have lost the battle and the war on this deal it is going to happen LOL



good luck

[Sean]

... Unfortunately, she has choosen 2 cm granite countertop, ... unfortunately, a worm drive won't do the granite

Actually, when we had full-thickness granite countertops installed in our condo, the installers made the cooktop cutout on-site with -- you guessed it, a worm-drive.  Of course, it requires a diamond blade, but it is done all the time.  Any professional granite installer should be able to do this for you after the fact with the granite already in place.  I would not have suggested it otherwise.

While we are on the subject, though, I will point out that there are at least two vendors who make half-thickness granite for boats and RVs.  One uses woven roving and epoxy for additonal support, and the other uses aluminum.  You might give this some thought, as the weight savings are considerable.  That's what we have.

-Sean
http://OurOdyssey.BlogSpot.com

[philiptompkjns]

As far is a built in, 120v, 2 burner... has anyone entertained the idea of buying a used regular smooth surface electric stove, removing the coils and internals. Then buying  2 of the 120V counter top units, take them  apart and install those internals into the built-in housing? I think I'd go for something like this if I were dead set on having a built in induction unit.
For me I think I'm going to go with exactly what sean has.

[Barn Owl]

The PO of my bus had put in a propane gas range. After trying to use it one time I knew why it looked new. It threw off so much heat you could hardly stand to be near it. The PO also made the kitchen too large and I needed more living/sleeping space. I knew the range had to go but I didn't know what to do to replace my ability to cook inside, even though we like to cook outside as much as possible, sometimes weather or time doesn't allow it. After reading Sean's post on induction cooking, I decided that was what I was looking for. I took out the old range and moved the entire cabinet and countertop section down to fill in the hole and free up some floorspace. I replaced the standard microwave with one that had convection cooking, and I ordered two portable induction cooktops.  I liked the idea of being able to store the cooktops out of the way when not needed and keep a clean clutter free counter that could be used for other things. I didn't get to do any trial runs before my big trip but thankfully it worked just as planned. The cooktops are an absolute dream to use, and I would NEVER go back to a gas stove inside the bus (My house is all propane so I know all about it.). Everything that has been said about induction cooking is true. In addition to being fast and efficient, they hardly produce any waste heat that can make the small space in a bus uncomfortable. I do not know why anyone doing a conversion would use anything else. Count me in the group that sings induction cooking praises.

[BG6]

We decided not to put in a built in stove top. I rather have the counter. We got a one burner induction that we can take out when we need it.

I went the other way.  I put in a GOOD cooktop (Jenn-Air downdraft with 4 burners plus BBQ grill), and when I need extra counter space I just set a stainless steel shelf on the stove.  The rest of the time, that shelf hangs on the wall behind the stove as a heat shield.

Thus, when I am hooked up to shore power, I can use electric hotplate, grill, etc (there is also a vent hood above the stove, which doubles as a shelf). 

[Skykingrob]

Sean
I have looked and looked for the website for the 1/2 thickness granite I read about it in the FMCA magazine. I tried the site given in the mag and got no response, so suspected they went belly up like so many other RV related companies have. If you have the URLs, I will try again, maybe it was in the FMCA mag wrong. Like you, I thought the aluminum base was the way to go.
I have neve seen anyone use a wrom drive to cut granite but did know it had to be a diamond blade, learned something new twice already today.

Rob
91 prevost LeMirage XL
Missouri